eResearch: the case of acute kidney injury

Excerpt

This year, an estimated 2 million people will die of acute kidney injury (AKI) worldwide [1]. Acute kidney injury is a serious complication of acute illness, typically occurring as a result of a combination of exposures like sepsis or nephrotoxins, and susceptibilities such as advanced age and underlying chronic kidney disease (CKD). Acute kidney injury has been shown to be independently associated with death and worsening of existing, or development of new, CKD [2]. The incidence of AKI and how it impacted survival was not known until recently. The reason was that AKI (or acute renal failure as it was known then) was a clinical diagnosis without a clear definition. While the condition was easier to recognize when it was severe, there was uncertainty as to whether early or milder forms of renal dysfunction were significant. However, in 2004, the acute dialysis quality initiative (ADQI) proposed new consensus criteria for diagnosing and staging AKI [3]. These criteria included changes in serum creatinine and urine output as the basis for diagnosis and staging and used the acronym RIFLE for three levels of severity (risk, injury and failure) and two outcomes (loss and end-stage kidney disease). These criteria have been subsequently adopted with minor modifications by the acute kidney injury network [4], and the modified RIFLE criteria have been endorsed by the kidney disease improving global outcomes (KDIGO) clinical practice guideline on AKI [5]. Indeed, this guideline attaches specific actions to the stages of AKI based on these criteria. These criteria for AKI have now been validated in thousands of patients [6], and their development has helped create a common epidemiological framework of reference. Furthermore, these criteria have increased the clinical appreciation that even small increases (>25 μmol/L) in serum creatinine are associated with greater risk of death and helped provide a structure for clinical trials both in terms of enrollment criteria and endpoints. …